1. Field of the Invention
The invention disclosed herein relates to energy storage cells, and in particular to techniques for providing an electric double-layer capacitor that is operable at high temperatures.
2. Description of the Related Art
Energy storage cells are ubiquitous in our society. While most people recognize an energy storage cell simply as a “battery,” other types of cells may be included. For example, recently, ultracapacitors have garnered much attention as a result of their favorable characteristics. In short, many types of energy storage cells are known and in use today.
As a general rule, an energy storage cell includes an energy storage media disposed within a housing (such as a canister). While a metallic canister can provide robust physical protection for the cell, such a canister is typically both electrically and thermally conductive and can react with the energy storage cell. Typically, such reactions increase in rate as ambient temperature increases. The electrochemical or other properties of many canisters can cause poor initial performance and lead to premature degradation of the energy storage cell, especially at elevated temperatures.
In fact, a variety of factors work to degrade performance of energy storage systems at elevated temperatures. Thus, what are needed are methods and apparatus for improving performance of an electric double-layer capacitor at elevated temperatures. Preferably, the methods and apparatus result in improved performance at a minimal cost.